The present invention relates to methods of applying an expandable sleeve to tubular workpieces to form a rim thereon and to rimmed tubular devices.
Paperboard tampon applicators comprising a pair of telescoping cylinders are well known in the art. For example, Wiegner et al., U.S. Pat. No. 4,412,833; Beastall et al., U.S. Pat. No. 5,087,239; Hinzmann, U.S. Pat. No. 4,755,164; Huffman, U.S. Pat. No. 4,573,964; Whitehead, U.S. Pat. No. 4,508,531; Neilsen et al., U.S. Pat. No. 5,683,358; and Iskra et al., U.S. Pat. No. 5,702,553 all teach various aspects of these applicators.
Tampon applicators, whether paperboard or plastic, generally incorporate surface features at the rear or gripper end to allow the user to more or less securely hold the applicator while ejecting the tampon from the opposite end of the applicator. While molded plastic applicators can generally have pronounced gripper ends by nature of their fabrication, the gripper end configuration of paperboard applicators and applicators formed from other sheet-like materials is more limited. For example, Wiegner et al. teaches a lightly grooved grip; Beastall et al. teaches a series of more pronounced grooves forming rings in the gripper end; Hinzmann discloses both a grip area having a reduced diameter and surface indentations; and Whitehead and Huffman both teach finger grip areas having substantially reduced diameter. Each of the finger grips taught in this prior art has a limited ability to prevent finger slip during ejection of the tampon.
More recent efforts have focused on using spinning techniques to manufacture outwardly disposed rim features. For example, Neilsen et al. discloses an apparatus for forming an outwardly projecting, integral fingergrip ring on a tampon applicator. One member of the apparatus rotates with respect another to form the curl. Iskra et al. discloses a method of fabricating paperboard tampon applicators having a diameter of less than about 25 mm and having an outwardly rolled finger grip. These techniques are similar and may offer very pronounced raised features on the tubular tampon applicator elements. However, both suffer from greatly increased mechanical complexity as they require simultaneous rotation and linear movements, the surface friction generated during the process can damage the surface of the materials, and the spinning techniques require significant clamping force to resist the rotational forces applied to the workpiece. Finally, these outwardly rolled products expose their, usually, unfinished inside surface to view in the rim. Neilsen et al. also illustrates in inwardly spun rim. This process fails to provide any raised feature while is suffers from most of the disadvantages described above. The complexity inherent in and the high frictional forces generated in the spinning processes results in higher capital equipment costs and increased likelihood of relatively high levels of scrap generation. Clearly, these traits are not desirable in a manufacturing process for low-cost products such as tampon applicators.
Therefore, what is needed is a robust, simple process for applying a rim to a tubular workpiece that generates an acceptable, low-cost product without requiring added heat energy (or dissipation thereof), and without the high axial loading caused by the rotational movement.
The present invention relates to an applicator device for inserting an object into a mammalian body cavity. The applicator includes a tubular member having a rim disposed at one end thereof. The rim has a shoulder projecting outwardly from the tubular member and a return margin directed inwardly from the shoulder distal the tubular member. The invention is especially useful in manufacturing paperboard applicators, such as tampon applicators.
In addition, the invention relates to methods of making a tubular device that has a rim and is capable of inserting an object into a mammalian body cavity. In one method, a sleeve having an expandable profiling surface is inserted into an end of the tubular member, and the profiling surface is expanded to form a shoulder projecting outwardly from the tubular member adjacent the end of the tubular member. The profiling surface is collapsed inwardly away from tubular member, and a return margin is formed directed inwardly from the shoulder, distal the tubular member.
In another method, return margin of the tubular device adjacent an end is folded inwardly and superposed on an inner surface of the tubular device adjacent the folded margin. A sleeve having an expandable profiling surface is inserted into the end of the tubular device, and the profiling surface is expanded to form the rim comprising a shoulder projecting outwardly from the tubular member and the return margin. As a result, the fold between the shoulder and the return margin defines an edge of the tubular member.
As used herein in the Specification and the Claims, the term xe2x80x9cexpandxe2x80x9d and variants thereof mean that the device modified by this term spreads or stretches out; is made greater in size, bulk, volume, or scope; or is enlarged. Thus, a segmented ring may expand by the individual segments spreading out and a ring may inflate or be deformed to acquire a greater outer circumference.
The outwardly flared rim of this invention provides a comfortable, finished edge to at least one member of an applicator, such as a tampon applicator. When formed on the plunger of such an applicator also having a barrel, the rim provides a stop to allow a user to determine when the contents of the applicator device have been fully expelled. This feature also prevents the plunger from being pushed or pulled through the barrel and being left behind in the body cavity. Finally, the rim provides an aesthetically pleasing edge to the applicator device.